<?php
	/*邓继松 2016-1-3 封装微信JS调用,  6-6日改为可ajax获取
	//注意是存到数据库，默认为id=1，以后修改
	//-----------------------*/
namespace Com;
class WechatJsapi {
  private $appId;
  private $appSecret;
  private $dbName;
  private $uid;

  public function __construct($appId,$appSecret,$dbName,$uid) {
    $this->appId = $appId;
    $this->appSecret = $appSecret;
	$this->dbName = $dbName;
	$this->uid = $uid;
  }

	//加入url用于分享静态页面
  public function getSignPackage($url=null) {
    $jsapiTicket = $this->getJsApiTicket();
	
	if(empty($url)){
    // 注意 URL 一定要动态获取，不能 hardcode.
    $protocol = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' || $_SERVER['SERVER_PORT'] == 443) ? "https://" : "http://";
    $url = "$protocol$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
	}
    $timestamp = time();
    $nonceStr = $this->createNonceStr();

    // 这里参数的顺序要按照 key 值 ASCII 码升序排序
    $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";

    $signature = sha1($string);

    $signPackage = array(
      "appId"     => $this->appId,
      "nonceStr"  => $nonceStr,
      "timestamp" => $timestamp,
      "url"       => $url,
      "signature" => $signature,
      "rawString" => $string
    );
    return $signPackage; 
  }

  private function createNonceStr($length = 16) {
    $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
    $str = "";
    for ($i = 0; $i < $length; $i++) {
      $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
    }
    return $str;
  }

  private function getJsApiTicket() {
    // jsapi_ticket 应该全局存储与更新，以下代码以写入到数据库中做示例
    
    //$data = json_decode(file_get_contents("jsapi_ticket.json"));
    $table = D($this->dbName);
    $data = $table ->where('uid='.$this->uid)->find();
	if(empty($data)){
		$data['uid'] = $this->uid;
		$table->add($data);
	}
    if($data['jsapi_time']  < time()) {
      $accessToken = $this->getAccessToken();
      // 如果是企业号用以下 URL 获取 ticket
      // $url = "https://qyapi.weixin.qq.com/cgi-bin/get_jsapi_ticket?access_token=$accessToken";
      $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
      $res = json_decode($this->httpGet($url));
      $ticket = $res->ticket;
      if ($ticket) {
        $data['jsapi_time'] = time() + 7000;
        $data['jsapi_ticket'] = $ticket;
        $table ->where('uid='.$this->uid)->save($data); 
      }
    } else {
      $ticket = $data['jsapi_ticket'];
    }
	
    return $ticket;
  }


  private function getAccessToken() {
    // access_token 应该全局存储与更新，以下代码以写入到文件中做示例
    //$data = json_decode(file_get_contents("access_token.json"));
    $table = D($this->dbName);
    $data = $table ->where('uid='.$this->uid)->find(); 
	
    if ($data['expire_time'] < time()) {
      // 如果是企业号用以下URL获取access_token
      // $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";
      $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";
      $res = json_decode($this->httpGet($url));
      $access_token = $res->access_token;
      if ($access_token) {
        $data['expire_time'] = time() + 7000;
        $data['access_token'] = $access_token;
        $table ->where('uid='.$this->uid)->save($data); 
      }
    } else {
      $access_token = $data['access_token'];
    }
    return $access_token;
  }

   private function httpGet($url) {
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_TIMEOUT, 500);
    // 为保证第三方服务器与微信服务器之间数据传输的安全性，所有微信接口采用https方式调用，必须使用下面2行代码打开ssl安全校验。
    // 如果在部署过程中代码在此处验证失败，请到 http://curl.haxx.se/ca/cacert.pem 下载新的证书判别文件。
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);   //不验证证书
    curl_setopt($curl, CURLOPT_URL, $url);

    $res = curl_exec($curl);   //获取
    curl_close($curl);

    return $res;
  }
}
	

	
?>